Diaphragm-type fluid control valves can provide controlled fluid separation and flow along a pipe-line, manifold or other piping network. Generally, the diaphragm-type valve includes a flexible diaphragm element to control fluid flow between the inlet and the outlet of the valve body. More specifically, in known diaphragm-type valves, the diaphragm element engages a seat formed within the valve body to separate the interior chamber of the valve body into three parts: (i) the inlet chamber which can hold the supply fluid, (ii) and outlet chamber which receives fluid from the inlet chamber for discharge out the outlet and (iii) a diaphragm chamber which can hold a fluid under pressure to urge and maintain the diaphragm element in the seated position. Upon release of fluid pressure from the diaphragm chamber, the diaphragm element can be displaced from the seated position by the pressure of fluid in the inlet chamber and fluid flow is permitted between the inlet and the outlet chambers. Known diaphragm elements and diaphragm-type control valves are shown and described in European Patent Application No. EP 0928917, U.S. Pat. No. 6,095,484 and U.S. Pat. No. 7,059,578, each of which is incorporated herein by reference in its entirety. Another known diaphragm-type valve is shown and described in Tyco Fire & Building Products data sheet TFP1305 entitled, “Model DV-5 Deluge Valve, Diaphragm Style, 1½ thru 8 Inch (DN40 thru DN200), 250 psi. (17.2 bar) Vertical or Horizontal Installation” (March 2004) as described in U.S. Provisional Patent Application No. 60/887,040.
One particular application for using known diaphragm-control valves is in the control of fluid flow between a fluid source under pressure such as, for example, a water main, and another fluid volume such as, for example, a network of pipes filled with a air. When a diaphragm-type valve is used to separate two fluid volumes that are to be independently pressurized, a check-valve is typically employed downstream of the diaphragm valve to form a seat against which the air or other fluid pressure may build downstream of the valve. For example, dry preaction fire protection systems employ a riser check-valve downstream of the diaphragm control valve to provide a seat for pressurizing the downstream network of pipes and sprinklers with pressurized gas. Such preaction system installations are shown for example in the following Tyco Fire & Building Product data sheets, each of which is incorporated by reference in their entirety and described in U.S. Provisional Patent Application No. 60/887,040 respectively: (i) TFP1420 “Preaction System with Model DV-5 Deluge Valve Single Interlock, Supervised—Electronic Actuation 1½ thru 8 Inch (DN40 thru DN200)” (September 2004) showing a riser check valve 16 in FIG. 1; (ii) TFP1415 “Preaction System with Model DV-5 Deluge Valve Single Interlock, Supervised—Dry Pilot Actuation 1½ thru 8 Inch (DN40 thru DN200)” (September 2004) showing a riser check valve 17 in FIG. 1; (iii) TFP1410 “Preaction System with Model DV-5 Deluge Valve Single Interlock, Supervised—Wet Pilot Actuation 1½ thru 8 Inch (DN40 thru DN200)” (September 2004) showing a riser check valve 14 in FIG. 1; (iv) TFP1465 “Preaction System with Model DV-5 Deluge Valve Double Interlock—Electronic/Electric Actuation 1½ thru 8 Inch (DN40 thru DN200)” (September 2004) showing a riser check valve 16 in FIG. 1; and (v) TFP1460 “Preaction System with Model DV-5 Deluge Valve Double Interlock—Electronic/Pneumatic Actuation 1½ thru 8 Inch (DN40 thru DN200)” (September 2004) showing a riser check valve 16 in FIG. 1. Effectively, the check valve defines for the system two pressures between the control valve and the network of sprinklers: (i) a first pressure down stream of the check valve equivalent to the supervisory air of the system; and (ii) a second pressure upstream of the valve between the control valve and the check valve that is different than the first pressure. The second pressure is typically atmospheric pressure to provide for a drain and/or an alarm port to comply with the installation or operational requirements under one or more standards such as, for example, Factory Mutual (FM) LLC publication, “Approval Standard: For Automatic Water Control Valves—Class Number 1020” (April 2007) (“FM Standard 1020”).